Photo-optical keyboard matrix (10) including a plurality of light transmitting optical fibers (12). The fibers are arranged in rows and columns with light generating means (14) disposed at the row terminations of the fibers and light receptors (16) are disposed at the column terminations of the fibers. The fibers are angularly cut at the matrix intersections of rows and columns to form an air prism. Individual key members, each provided with light blocking and unblocking means are movable into and out of the air prism area effectively blocking and unblocking light from generator to receptor thus providing optical keyboard switching apparatus.

Fiber wrap keyboard and switch
Application Number
Publication Number
Application Date
March 15, 1983
Publication Date
September 29, 1983
Free James E
Ely Richard I
Mosier Carl E
Subbarao Wunnava V
CHUNG Edmund M
Burroughs Corporation
G02B 06/35
View Original Source